摘要
针对外辐射源雷达由于采用非合作照射源而导致的目标信噪比低、易被直达波和多径等干扰掩盖等目标探测难题,本文研究可增强回波信噪比的可重构智能表面(RIS)辅助外辐射源雷达系统和相应的目标参数估计方法。在分析建立RIS辅助的外辐射源雷达系统模型和信号模型的基础上,首先研究外辐射源雷达系统配置下RIS的设置方法,建立以提升接收信号的信杂噪比(SCNR)和保证直达波接收功率为准则的RIS反射系数优化问题,并理论推导RIS反射系数的全局最优解,从根本上解决弱目标探测问题;然后,研究RIS辅助下外辐射源雷达的信号处理方法,提出了一种基于时变RIS与稀疏重构的目标多参数估计方法,可实现对目标时延、速度和方位等参数的同时估计;最后实验验证了所提方法的有效性和优越性。
Aiming at the challenges of low target signal-to-noise ratio(SNR),susceptibility to direct wave and multipath interference,and other target detection problems arising from the use of non-cooperative illumination sources,this paper studies the reconfigurable intelligent surface(RIS)-assisted passive radar system which can enhance the echo SNR and the corresponding target parameter estimation method.On the basis of analyzing and establishing the RISassisted passive radar system and signal model,firstly,the RIS configuration within the passive radar framework is explored.The RIS reflection coefficient optimization problem is established to improve the signal-to-clutter-plus-noise ratio(SCNR)of the received signal and ensure the direct wave receiving power.The global optimal solution of the RIS reflection coefficient is deduced theoretically,and the problem of weak target detection is solved fundamentally.Then,the signal processing method for RIS-assisted passive radar is investigated,and a multi-parameter estimation method based on time-varying RIS and sparse reconstruction is proposed,which can estimate the target parameters such as time delay,velocity,and azimuth simultaneously.Experimental results demonstrate the effectiveness and superiority of the proposed method.
作者
赵志欣
李周章
林应运
陈远帅
ZHAO Zhixin;LI Zhouzhang;LIN Yingyun;CHEN Yuanshuai(School of Information Engineering,Nanchang University,Nanchang 330031,China)
出处
《雷达科学与技术》
北大核心
2025年第5期529-539,550,共12页
Radar Science and Technology
基金
国家自然科学基金(No.62261036)
江西省自然科学基金(No.2022BAB202003)。
关键词
外辐射源雷达
可重构智能表面
目标多参数估计
稀疏重构
passive radar
reconfigurable intelligent surface(RIS)
target multi-parameter estimation
sparse reconstruction
